<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        div{
            border: 1px solid #000;
        }
        #mainDiv{
            width: 1000px;
            height: 600px;
            margin: auto;
        }
    </style>
</head>
<body>
    <div id="mainDiv">
        <div style="height: 80px">
            <h1>标题栏</h1>
        </div>

        <div style="height: 515px;display: flex;">
            <div style="width: 150px;height: 512px;">
                导航栏<br>
                <a href="news.html" target="contentFrame">新闻</a><br>
                <a href="sport.html" target="contentFrame">体育</a>
            </div>
            <iframe name="contentFrame" width="840" height="512" src="2.html">

            </iframe>
        </div>
    </div>
</body>
</html>